Ralph s



June 2 2 1926.

R. s; TYLER THROW-OFF MEcXjA IsM 1 0 PRINTING PRESSES Filed Feb. 12, 1925- 'INIVEA'ITOR;

BY @y Patented June 22, 1926.

UNITED STATES PATENT OFFICE.

RALPH S. TYLER, OF CLEVELAND HEIGHTS, OHIO, ASSIGNOR TO THE CHANDLER PRICE COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

THROW-OFF MECHANISM FOR PRINTING PRESSES.

Application filed Tiebruary The use of throw-off mechanism in platen printing presses or presses of the so-called Gordon type is quite familiar and well understood, the object of such mechanism being so to shift the position of the bed that without interrupting its oscillation, or, 111 other words, stopping the press, the form carried by said bed will nevertheless be prevented from contacting with the platen. This shifting is ordinarily accomplishedby eccentrically connecting the bed operating means with the ends of the so-called back shaft which is suitably journaled in the bed, such shaft being rockable so as to vary in effect the throw of said operating means. In the operation of a press, it is necessary to use such throw-off mechanism whenever the sheet on the platen slips or is improperly adjusted, as well as on other occasions, and it accordingly becomes important that said mechanism be not only simple in con struction but so designed as not to interfere with the normal operation of the press.

Various difficulties known in the trade as jumping and winking are as a matter of factattributable to the present construction of throw-off mechanism, being occasioned by a slight rocking movement of the aforesaid back shaft even when the throwoff mechanism is in its inoperative position.

,One object of the present invention, ac cordingly, is to provide a mechanism that will insure against such incidental and undesired oscillation of the back shaft while at the same time said shaft maybe easily rocked whenever it is desired to throw the bed off and avoid contact of the form with the platen. To the accomplishment of the foregoing and related ends, the invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims, the annexed drawing and the following description setting forth in detail certain mechanism embodying the invention, such disclosed means constituting, however, but are of various meehanicaf in.

12, 1925. Serial No. 8,716.

principle of the invention may nism taken on the planes indicated by the lines 22 and 38, Fig. 1, respectively.

The press is of familiar construction, comprising a platen 1, suitably supported on a frame 2, and an oscillatory form-carrying bed 3 that is swung toward and away from said platen through the medium of cranks 4- and connecting rods or side arms 5. The cranks 4, of which there are two, one on each side of the press, are in fact pins that project outwardly from disks 6 mounted on the corresponding ends of the front shaft 7, and the rear ends of the arms 5 are connected to the bed 3, as hereinbefore indicated, through the medium of outwardly projecting eccentric pins 8 on the corresponding ends of back shaft 9. The ink distributing disk 10, form 11 and form rollers 12 require'no special description. The throw-off mechanism of present interest, as has also been hereinbefore indicated, is designed to rock the back shaft 9 so as to shift the position of the eccentric pms 8 and thereby change the position of bed 3 with form 11 relatively to crank pins. 1. In Fig. 1, the parts as shown in full lines occupy the on position in which the form' Wlll contact with the platen, while the dotted;

position of partsindicates the platen in off position. 7 p

The throw-off mechanism comprises a handled lever 15 that is oscillatorily attached at an intermediate point 16 to one side of the frame 2. Similarly oscillatorily at tached to such frame side at a point 17, located rearwardly with respect to point 16, is a double arm lever 18, the upper end of phichis connected with the low end of lever 15 by means of a'hnk, 19. The new and and lever 18 sliding; pivctai sea:

9 and radially projecting therefrom.

1 shaft being approximately through an arc of90'degrees and in a counter-clockwise direction in rocking the shaft from such on to its oil position.

For the purpose of securing the slidable pivotal connection between the lower end of lever 18 and the one arm of the bell crank 20, such end is provided with a stud 23 that engages with an elongated slot in said bell crank arm. Said bell crank may accord- 20 ingly be rocked through substantially the same angle as hack shaft'E), the pin 23 traveling in and then out along; slot so that at the initi .ition of the rocking movement, whether from ott to on position of the parts,

or vice versa, the pin always occupies its outermostposition. It will further be noted that, as clearly shown in Fig. 2, the bell crank is oscillatorily supported upon the same axis, in fact upon the same shaft or rod 25 whereon'bed oscillatorily mounted. As a result of this feature of construction, therewill be substantially no movement impartedt'o the link and lever system that connects said bell crankwith back shaft 9 5 rel'ativelyto the bed i;self when the latter is oscillate'd with said system in on position. In" other words, the back shaft is held againstfa'nyslight' rocking movement in its hearings in. this position of the parts with the result that the eccentric pins are for all intents and purposes lined in the bed, thus insuring smooth, easy to and fro movement of the latter when'the press is running normally;

It will further-be noted that in the on position of the par-ts, the arm of hell crank 20,-wherewith link 21 is connected, is swung far enough forwardlyto bring said'arm and the point of pivotal connection between the same and said link substantially in a line joining thecenter of said bell-crank and the end of arm This makes for rigidity, any tendency the back shaft to roll being resisted by a straightline pull on the parts in question.- Finally, by reason of the sliding pivotal conn'ect'ion between lever 18 and the other arm of the bell-crank, the latter is elfecti'vely locked in both its off and its on position, the lever being; arranged to swing through an are (slightly over 90) sufficient to. msure'against accidental breaking of the joint inwardly.

@ther'modesof applying the principle of my invent ionmay be employed instead of the one explained, change being made as regards the mechanism herein disclosed, provided the means stated by any of the following claims or the equivalent of such stated means be employed.

I therefore particularly point out and distinctly claim as my invention 1. In a platen printing press, the combination with the oscillatory bed, a back-shaft journaled in said bed and side-arms eccentrically connected with said shaft; of means for rocking said shaft inorder to prevent the making of an impression, said means including; an oscillatory lever-member mounted to swing onan axis substantially coaxial with the axis of said bed, a lever projecting; from said'shaft, and a link connecting; said levers.

2. In a platen'printingpress, the combination'with the oscillatory bed, a back-shaft journaled in said bed EUKlShlO-dlillfi eccentrically connected with said shaft; of means for rocking); said shaft in order to prevent the making ofan impression, said means including an oscillatory lever-member mounted t'o swing on an axis substantially coaxial with-the axis of said bed, a lever projecting; fion'rsaid shaft, anda link connecting said levers, said link and the point of pivotal connection between the same and said Firstnamed lever lying substantially in a line joining the axis'of said'lever and the end of the'lever projecting from said shaft in the impression-on position of the parts.

3. Ina platen p'rinting'press,tl1e combination with the oscillatory bed, a back-shaft journaled' in saidh'ed' and'side-arms eccentrically connected-with said shaft; of means for rocking saidshaft in order to prevent the making-of animpression, said-means ineluding a dell-crank oscillatory about substantially the same axis as said bed, a lever projecting from said'shaft, a link connecting' one arm of said hell-crank with said lever, and another lever having a sliding, pivotal connection with the other arm of saidbelhcrank, whereby the latter may be rocked as well' as locked in either limiting position. 7

4. In a=platen printing press, the combination wit-lrthe oscillatory bed, a back-shaft jonrnal'ed in said hed and side-arms eccentrically connected with saidshaft; of means for rocking said shaft in order to prevent the making of an impression, said means including; a bell-crank oscillatory about substantially thesame axisas said lied, a lever projecting from saidshaft, a link connecting one arm of said bell crank with said lever, and another lever having apin on its end, the other arm of said bell-crank having a slot in sliding pivotal engagement with said pin.

5. In aplatenprinting press, the combination with-the oscillatory bed, a hack-shaft journaled in said bed and side-arms eccentrically connected with said shaft; of means one end,. the other arm of said bell-crank for rocking said shaft in order to prevent having a slot in sliding pivotal engagement 10 the making of an impression, said means inwith said pin, a handled operating lever, eluding a bell-crank oscillatory about suband a link connecting the" same with the 5 stantially the same axis as said bed, a lever other end of said double-arm lever.

projecting from said shaft, alink connect- Signed by me this 9th day of February, ing one arm of said bell-crank With said 1925. lever, a double arm lever having a pin on RALPH S. TYLER. 

